Pneumatic hammer.



F. I. SCHROEDER.

PNEUMATIC HAMMER.

APPLICATION FILED APR- 8.1915.

1,230,802.. Patented June 19, 1917.

gum/wk FRANK J scHRoEDER UNITED SAESPATENT onnion.

FBANK J. SCHROEDER, OF ALTOONA, PENNSYLVANIA, ASSIGNOR T0 NORMAN E. GEE,

0F ALTOONA, PENNSYLVANIA.

PNEUMATIC HAMMER.

To all whom it may concern: Be it known that FRANK J. SoHRonDnR, a citizen of the United States, residing at Altoona, in the county of Blair and State of Pennsylvania, has invented certain new and useful Improvements in Pneumatic Hammers, of which the following is a specification.

This invention relates to an improvement I in pneumatic hammers, and has particular reference to a novel tool retainer therefor. In connection with the use of pneumatic hammers, it is well known that if the trigger is accidentally pressed when the tool is not held up to its work, that the tool is discharged with the force of a projectile from a gun, and within a comparatively close range may have a deadly efl'ect. Accordingly, the present invention contemplates a safety construction for pneumatichammers which will efiectively lock the tool in place or restrain the same within the barrel, though at the same time permitting it to exercise its normal functions when in use.

Primarily the invention has in view a plurality of segmental tool engaging and looking plates which restrain or'prevent the tool from being shot from the barrel of ahammer, and which are held in place by a single holding element that may be easily manipulated to either lock the segments in position or remove the same for replacing or reversing. In this latter connection, the inventionprovides a plurality of button set locking elements which are readily interchangeable and reversible to present fresh unworn surfaces. That is to say, the presenttype of locking elements involve opposite flat surfaces one of which is subjected to the continuous intermittent impact of a shoulder on the tool, due to the piston subjecting the latter to the usual hammer blow. This face of the segment will naturally wear down, while the opposite surface is fresh and unworn. Thus by merely reversing the position of the segments a new surface may be presented. W

Another object ofv the invention is to provide a construction which will not add any appreciable extra weight or bulk to the barrel of the hammer, thus permittingthe operator to easily manipulate the tool in close quarters, such as are often encountered in Specification of Letters Patent. Patented J 1111 19, 1917, Application filed April 8, 1915. Serial No. 20,080. V

the construction of modern steel cars, steamships, and structural iron buildings. In connection with this feature of the invention, the same proposes to countersink the hold ing or clamping means for the locking segments so that the same will not be in the way under any condition of use of the tool.

A further object of the invention is to provide a novel tool or button set lock possessing strength and rigidity, and which will so look or restrain the tool in place that it will be impossible to manually withdraw the tool, that is pull or slide the same out of the barrel, without removing the locking segments, thus eliminating any possibility of the tool being accidentally discharged, as may be the case where the tool is held in the barrel by yielding, holding, or retaining means.

A still further object of the invention is toprovide simple and practical safety locking elements that may be economically manufactured, and made in a uniform and standard size, thus facilitating their application to hammers now in use, and enhancing their value in connection with newly constructed hammers, because they are readily reversible and interchangeable.

With the above and other objects in view which will more readily appear as the nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the inventionis illustrated in the accompanying drawings, in which Figure 1 is a plan view of a pneumatic hammer showing my invention applied thereto.

Fig. 2 is an enlarged detail view of the tool head or button set showing the i1n- Fig. 7 is an end View of one of the looking keys. 1

Similar reference characters designate corresponding parts throughout the several 'figures of the drawings.

In carrying out the invention, it is proposed to utilize the same in connection with standard types and designs of pneumatic hammers, and owing to the simplicity of the safety locking elements employed in connection with the present construction, the invention may be easily adapted to hammers now in rise and not equipped with a safety device for restraining the tool head. 7

By reference to the several figures of the. accompanying drawings, it will be observed that the reference numeral 1 designates the that is'adapted to be engaged by one of the locking elements or keys generally referred to as '6.

In order to equip the barrel 1 for receiving and properly positioning and holding the keys 6, the same is preferably formed at one end with an 'aiinular countersunk clamp receiving groove 7 whose opposite side edges 8 and 9 are beveled "as clearly shown in Fig. 1 to facilitate the application of the holding element 10 for the locking keys, hereinafter more fully referred to. The said groove 7 is providedpreferably at diametrically *opp'osite points, with segmental key receiving sockets 11 which are provided with a bottom opening 12 communicating with the interior of the piston barrel 1.

W ith particular reference to theloeking keys 6, which interlock with the tool head. 2 to restrain the movements thereof, it will be observed that the same are of substantially flat formation, and include an elliptical head portion 13 carrying a depending keeper shank or tenon 14; which constitutes a stop or abutment to prevent the tool head from being discharged from the barrel. This type of locking key is particularly advantageous since it provides opposite wear faces and Men the keeper sh'an k H, thus rendering the key capable of being reversed, and thereby insuring greater wear and longer life therefor. The bottom edge 17 of the keeper shank 1% is arched or curved so as to be capable of slidably fitting over the portion of the shank 3 within the keeper recess 1, as will be apparent from Fig. 3.

From the foregoing description, it will be evident-that the barrel 1 of the pneumatic tool H is formed with key receiving sockets 11 which are adapted to receive the reversible and interchangeable keys 6 in such a manner that the depending keeper shank let thereot'passes through the bottom opening 12 of the socket to engage within the angular keeper recess a on the tool shank 3. When the keys 6 are thus in position, they are locked against displacement by means of the spring retaining'ring 10 which fits fiushly in the groove 7 so as to be entirely out of the way and not hinder the manipulation of the tool in close quarters. For the purpose of fa'cilitatiiigthe manipulation of this retaining ring 10, the adjacent free end portions 19 are bent upwardly to constitute finger grips, thus enabling the operator to easily shift the ring over the beveled side 9 of the groove 7 onto {the external surface of the barrel 1 whenit is desired to effect a removal of the locking keys. I 1

The particular construction at the end of the barrel 1 also materially facilitates the assembling and taking apart of the several parts constituting the present safety construetion. That is'to say, after the locking keys 6 are placed in'p'osition in their respective key sockets 11, the spring-retaining ring 10 may be easily slipped over the beveled edge 18 and snapped into the groove 7 after having passed over the beveled edge 8. When it is desir'ed to remove the keys 6 for the purpose of changing tools, replacing keys or reversing the'same,it is only necessary to grasp the ring 10 so that it may be shifted onto the exterior surface of the barrel over the beveled edge 9. I

With regard to the keys '6, and their reversibility, it will be apparent that this feature of the invention is of much importance from a practical standpoint When the keys are in normal locking or tool-head restraining position, the rear face 16, for instance, ofthe shank portion 14 is exposed to the continuous intermittent imp'act 'ot the shoulder 5 of the tool head, due to the latter being subject to the usual ham1ner blow by the piston within the barrel 1. In a short time, the face- 0f the shankp'ortion of the key thus exposed will become worn, while the opposite face 15, for instance, is' fresh and entirely unworn. Thus, by simply removing the ring 1'0 and reversing the position of the key, a fresh unv'vorn face may be presented to the shoulder "5 of the tool-head shank. Thesekeys 6 are not only reversible, but because of their novel design and construction at the end of the piston barrel 1, they are readily interchangeable, thus presenting another feature of practical importanc'c.

Without further description, itis thought that the various features and advantages of the present invention will be readily apparent, and it will of course be understood that minor details of construction may be resorted to without departing from the spirit of the invention or scope of the appended claims.

I claim:

1. A pneumatic hammer including a barrel provided with radially arranged key receiving openings of rectangular cross section and having their long diameter arranged at right angles to the axis of the barrel, said openings also being of a flaring form producing opposite seating faces, a tool-head having a stem formed with spaced apart shoulders, interchangeable and reversible keys of rectangular cross section and having similar flat wear faces upon both sides, and also having opposite shoulder portions engaging said seating faces and locking tenons extending through the key receiving openings into the space between the shoulders on Copies of this patent may be obtained for the tool-head stem, and retaining means for holding said keys in position.

2. A pneumatic hammer including a barrel having angular key receiving openings of flaring form producing opposite seating faces, a tool-head having a shank formed with spaced apart shoulders, interchangeable and reversible locking keys each comprising a segmental head portion and a depending keeper shank of rectangular cross section for extending through the key receiving openings into the space between the shoulders on the tool head stem, and means for holding the said keys in position.

In testimony whereof I afiix my signature in presence of two Witnesses.

FRANK J. SCHROEDER.

Witnesses:

N. E. GEE, GEO. WIGAND.

five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

